Which Pulley And Are The Standard Injectors Ok?

[tidypug 5 2 Cars]

Hi all,

I'm going to be putting my inlet cat cam in my Mi this weekend and have been thinking about which pulley will be best to use, i've been reading that pulley 2 or 3 but am not sure as that was for the lower spec engine. MY spec is basically standard but with the uprated inlet cam, so which pulley will give the most power? I'm not too bothered if i loose some bottom end torque as it will lose some down to the cam. I just want to maximinse my power using the standard pulley's.

 

Secondly is the injectors. As i'm running standard injection would there be any need to change them as if i remember correctly the standard Mi injectors are running as much as they can at 180 bhp, which my Mi will hopefully be quite near (going by taffycrooks evidence). I'm not even sure i could change them, i'm just curious.

[DrSeuss 0]

Uprating your injectors is a bit of a bodge, but thats always going to be the case on standard management. Your best bet is to uprate them slightly but this will cause a poor idle quality as there is no feedback loop on an mi engine (no lambda sensor).

 

You could up the fuel pressure slightly causing similar problems but being a slightly more incremental affair (up the fuel pressure until it no longer runs lean at top end).

 

Anything will be a bodge and there is no easy way around it, you can solve the problem but at the cost of slightly less driveability.

[tidypug 5 2 Cars]

My Mi runs a lambda sensor so would this change anything?

[Ryan 99]

Not really. It's a common misconception that the lambda can compensate for injector size. In fact all the lambda is used for is trimming back the fueling while crusing to give better mpg and lower emissions. At idle and most of the rest of the time it's simply ignored.

[petert 587]

#3 pulley is advanced 3 crank degrees over the #2. So it has the same effect as putting on verniers then advancing them 3 deg. The position of your cam should be written on the spec. sheet. The two pulleys position the maximum lift point of the std. inlet cam as follows:

#2 - 114 deg. ATDC

#3 - 111 deg. ATDC

 

Maybe your new cam is supposed to be positioned at 108 deg. What will you do then? You could buy an offset key from me, that will advance the cam a further 3 or 4 degrees.

 

It's been my experience that the std. ECU map has plenty of fuel in reserve to drive a mild inlet cam. With a cam the same as Taffy's and 10.8:1, the AFR runs to approx. 12.7-12.8:1 at load.

Edited October 27, 2005 by petert

[tidypug 5 2 Cars]

Ok so i'll be good to leave the injectors alone as they can cope just fine. I've scanned in the data sheet that cam with my cam,

 

.

 

Is this any help? It doesn't mean anything to me so which pulley will give me the most power?

[petert 587]

#3

[tidypug 5 2 Cars]

thank you

[C_W 3 1 Cars]

What about pulley "no.4"?

[B1ack_Mi16 67]

What about pulley "no.4"?

 

It "doesn't exist"

Strange this one, but noone seem to know that.. I've never seen one myself either.. But it's probably not too hard to measure it?

[Kev-G 1]

It "doesn't exist"

Strange this one, but noone seem to know that.. I've never seen one myself either.. But it's probably not too hard to measure it?

 

Certainly exist - We've got several....

[B1ack_Mi16 67]

Certainly exist - We've got several....

 

That's why I put it in " " signs...

[C_W 3 1 Cars]

I think this originates from BX 16vs? and think that its actually fitted to the exhaust pulley rather than the inlet?

 

So would a 3 inlet and 4 exhaust be useful?

[Kev-G 1]

That's why I put it in " " signs...

 

Yeah, but you then went onto say that no-one seems to know that....Must have been lost in translation.

[C_W 3 1 Cars]

I thikn he meant its not documented anywhere in the peugeot manuals and nobody seems to know about them. But they are probabl a citreon one; I remmeber a thread about someone saying the BX makes more power to compensate for the hyrdaulic pump off it but not sure if that is true.

[Ahl 4]

I thinks thats right. The exhaust cam pulley is advanced a little more. Dunno if its a 4 though - I'll have a look at mine later.

[B1ack_Mi16 67]

I thinks thats right. The exhaust cam pulley is advanced a little more. Dunno if its a 4 though - I'll have a look at mine later.

 

I butchered a 1987 BX 16v last year, and that one had (2) pulleys on both inlet and exhaust..

[Kev-G 1]

I thikn he meant its not documented anywhere in the peugeot manuals and nobody seems to know about them. But they are probabl a citreon one; I remmeber a thread about someone saying the BX makes more power to compensate for the hyrdaulic pump off it but not sure if that is true.

 

But a hydraulic pump is no diff. from a P/S pump?

 

I don't recall ever seeing a #3, but we've certainly seen engines with 2*#2, and #2 + #4 - I can't remember how these were configured.

[B1ack_Mi16 67]

But a hydraulic pump is no diff. from a P/S pump?

 

I don't recall ever seeing a #3, but we've certainly seen engines with 2*#2, and #2 + #4 - I can't remember how these were configured.

 

The 147bhp ones that's quite common here do all have (3) on the inlet due to lower compression.

[Kev-G 1]

The 147bhp ones that's quite common here do all have (3) on the inlet due to lower compression.

 

Ah - Don't deal with the 'inferior' engines!!

[Anthony 1,003]

Both of the BX 16v engines that I've had have had both "2" pulleys on them, so I don't think it's that. I was under the impression that the actual exhaust cam itself was different on the BX engines, and the cams different again on the Mi16x4 engines?

[C_W 3 1 Cars]

Dunno, mine is out a 90H-reg BX 16v, tho.

[petert 587]

Both of the BX 16v engines that I've had have had both "2" pulleys on them, so I don't think it's that. I was under the impression that the actual exhaust cam itself was different on the BX engines, and the cams different again on the Mi16x4 engines?

 

BX16V and Mi16x4 have indentical exhaust cams

[sorrentoaddict 1]

how about mambo "nr. 5" ?

 

[sorrentoaddict 1]

if anyone is still interested, here is the definitive finding on the #4 cam pulley:

 

1) it is fitted on late-ish BX16v with late D6C non-CAT engines (CR 10.4 : 1)

 

2) it is used ONLY on the Inlet cam

 

3) the Exhaust cams on these late 160 HP non-CAT engines use a #2 pulley

 

4) the Exhaust cams on ALL BX 16v engines are DIFFERENT themselves

(more duration)

 

5) the #4 pulley has a cca. 139 deg. "separation", which makes it WAY more retarded than #3 and #2. It is used for better top-end and better cylinder filling at high RPM. I guess that is one of the explanations why these late 160 HP BX16v are so unbelievably fast as a top-speed performance...

 

It can also make a dramatic improvement if used as an Exhaust pulley on, say, a hillclimb or rally engine, where a healthy mid-range is needed.

 

 

Cheers

 

 

AG